In telecommunications, a Layer 2 (L2) switch may use addresses for computers and other networked electronic devices for sending and receiving packets of information. L2 forwarding traditionally follows Institute of Electrical and Electronic Engineers (IEEE) standards to provide emulated local area network (ELAN) services using bridging. In L2 bridging, methods such as standard Spanning Tree Protocol (STP) may provide a way for the local area network to maintain redundant links while preventing bridge loops. Variations of STP include rapid spanning tree protocol (RSTP) and multiple spanning tree protocol (MSTP).
In implementations of STP, RSTP and MSTP, table entries in an L2 switch forwarding table may be created for various destinations, where each entry corresponds to a path to the destination, based on the active links that exist through the network. If the L2 switch receives a packet, it may forward the packet to a destination coupled to the active links, based on the information in the table entries about where the destination is located. If one of the active links goes down, a new path may be calculated for the various addresses based on the existing active links.
In 802.1ad compliant switching systems, xSTP is implemented in a centralized format. In such a switching system with a distributed architecture including multiple individual switching units, it is difficult to scale to a large number of switching units because the xSTP protocol is processor-intensive and becomes increasingly processor-intensive with increasing switching units.
The subject matter claimed herein is not limited to embodiments that solve any disadvantages or that operate only in environments such as those described above. Rather, this background is only provided to illustrate one example technology area where some embodiments described herein may be practiced.